Stacking machine with flow control system



A ril 21, 1970 R. SPENCER STACKING MACHINE WITH FLOW CONTROL SYSTEM 3 Sheets-Sheet 1 Filed 001:. 6, 1967 INVENTOR. 205527 A. 525M654 April 21, 1970 R. L. SPENCER 3,507,492

STACKING MACHINE WITH FLOW CONTROL SYSTEM Filed Oct. 6. 196'? 3 SheetsSheet 2 Ta cam/7'52 INVENTOR. @0559? 1.52am? April 1970 R. L. SPENCER 3,507,492

STACKING MACHINE WITH FLOW CONTROL SYSTEM Filed Oct. 6, 1967 3 Sheets-Sheet 5 120 a f 07 122 g 136 40/ 4 120 f0 wa 2035271. da a me 5 g BY M 1% E 40 United States Patent 3,507,492 STACKING MACHINE WITH FLOW CONTROL SYSTEM Robert L. Spencer, Burbank, Califl, assignor, by mesne assignments, to AB Bonnierforetagen, Stockholm, Sweden, a corporation of Sweden Filed Oct. 6, 1967, Ser. No. 674,073 Int. Cl. B65h 29/68, 29/12, 31/00 US. Cl. 271-68 Claims ABSTRACT OF THE DISCLOSURE BACKGROUND OF THE INVENTION Field of the invention This invention relates to stacking machines for sheet materials such as newspapers and the like.

DESCRIPTION OF THE PRIOR ART Newspaper stackers are known in which papers pass from a conveyor onto vertically moving racks. A primary object of such stackers is to automate the stacking of papers and thus eliminate a serious bottleneck to efficient and economical production and distribution of newspapers. Unfortunately, stackers as heretofore known are characterized in that they cannot be relied upon to stack true the various thicknesses and types of folded papersdailies, Sunday editions, tabloids, magazine supplements, etc.

Typically, papers enter a rack in a free fall, and slide on papers'they come to rest on. Accordingly, the various edges of the papers throughout a stack are not aligned. Another frequent occurrence is that thin papers, e.g., special inserts, will double over upon entering a rack, and the result is a stack with many crumpled papers throughout. Such results frustrate the primary aim of the stacker, because manual labor must be emloyed, e.g., to true up the stack, eliminate or replace crumpled pieces, etc.

SUMMARY OF THE INVENTION Stacker structure is improved to insure control of the flow and stacking of sheet materials so as to substantially eliminate problems with which prior art stackers could not cope. Means are provided to shape papers so they become structural elements to facilitate their own stacking, and to insure that, regardless of the thickness and number of folds in papers being stacked, they are stacked so they are trued up, and there is no need for the amount of manual labor heretofore required for the so-called automatic stackers.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation view of an improved stacker in accordance with my invention;

FIG. 2 is an end elevation view taken along the lines 22 of FIG. 1;

FIG. 3 is an enlarged view in elevation taken along the lines 3-3 of FIG. 1, showing more clearly my means for initiating a bow in papers as they enter a bucket;

FIG. 4 is a top plan view taken along the lines 4-4 of FIG. 1, showing more clearly the arrangements of the parts of my invention over which papers are processed to be stacked;

FIG. 5 is a side elevation view of the portion of the apparatus shown in FIG. 4, showing their cooperative functioning in feeding and stacking papers;

FIG. 6 is an enlarged sectional view of the midportion of the bucket shown in FIG. 3;

FIG. 7 is an enlarged top plan view of one of the upper flow guides shown in FIG. 4;

FIG. 8 is an enlarged top plan view of one of the arc modulator elements of FIG. 4, showing more clearly how the elements can be adjusted to alter the are imparted to papers as they pass onto a bucket;

FIG. 9 is a top plan view of the portion of the left hand side of FIG. 4 .wherein the papers pass onto the bucket, showing the bow enlarger and retainer positioned on one side of the center of the buckets opposite the edge folds of papers passing into the buckets;

FIG. 10 is an enlarged view in perspective of the elements shown in FIG. 9, showing papers being stacked in a bucket as it passes along the bow enlarger and retainer; and

FIG. 11 is an end view of the apparatus shown in FIG. 10, to aid in explaining the function of the bow enlarger and retainer.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1 and 2 a newspaper stacker is shown having a housing 10 which supports a plurality of buckets or racks 12 for vertical movement in the path of newspapers conducted thereto from a conveyor, the final portion of which is indicated at 14.

The racks 12 are supported for movement by a chain and sprocket mechanism, indicated in dotted lines by the chain 16 and sprockets 18-20. One of the sprockets 20 is driven by a motor 22, via a slip clutch 24. As indicated, a rheostat 26 is connected between the motor 22 and a generator 28 that is driven from the conveyor 14, as shown by mechanical coupling from the generator 28 to one of the rollers 30 which serve to convey the papers to the stackers. The speed of rotation of the rollers 30, i.e., the speed at which the papers are conveyed to the stacker, can be varied, as can the speed of operation of the racks 12.

Referring to FIG. 10 along with FIGS. 1 and 2, each rack has a back and seat formed of a plurality of L- shaped bars 40 which are supported along bar 42 in fixed spaced relation, and extending outwardly from the end of bar 42 are rollers 44, 44. Each of the rollers 44 is adapted to move within an associated one of the rails 46 (FIG. 2) which, as best seen in FIG. 1, have an upper inclined portion and a lower vertical portion. Thus, the chain drive 16 causes the rear legs of the bars 40 to move downwardly parallel to the incline, and then move to a vertical position. Upon continued downward movement of the rack 12, the horizontal legs of the bars 40 pass between rollers 48 which are rotatably supported in brackets 50 that are anchored at the front end of the stacker, and which are driven at 52 from a motor 54 so as to rotate in the same direction. Thus, with papers stacked on a rack 12 as indicated in FIG. 1, and upon the horizontal legs of the bars of the rack passing between the rollers 48, the papers are conveyed to the side of the stacker, as onto an additional roller conveyor (not shown) to a location where they can be collected.

As further indicated in FIG. 1, continued downward movement of the rack from which the papers were removed results in the vertical legs passing below and between the rollers 48 as the chain drive carries the rack downwardly and around the lower sprocket 20 for its return movement.

In FIG. 1, the upper portion 60 of the stacker into which the papers are fed from the conveyor 14 is designated an infeed section through which papers pass from the conveyor 14 to reach the racks 12. Referring to FIGS. 4 and 5 along with FIGS. 1 and 2, the infeed section 60 includes a lower pair of rollers 62 which are connected by spring wire 64 for rotation in unison. The infeed section 60 also includes upper sets of pulley wheels 65, 66, 68, wherein respective spring wire belts 70, 72 connect the pulley wheels 65, 66 and 66, 68. The rollers 62 and the pulley wheels 65, 66, 68 are driven at a constant speed from a constant speed motor 74. To this end, the motor 74 is shown to drivingly engage the roller 62, which in turn is mechanically coupled to the pulley wheel 66, such mechanical connection being such as to assure that the rollers 62 and the pulley wheels rotate in opposite directions, i.e., that the rollers 62 in FIG. 5 rotate counterclockwise, and the pulley wheels 65, 66, 68 rotate clockwise. As will be seen in FIG. 5, papers passing from the conveyor 14 pass along the wire belts 64 and under the pulleys 66.

As previously indicated, the conveyor 14 may operate at different speeds. However, when the papers pass onto the wire belts 64, they are traveling at a constant speed. Further, the speed of the motor 74 is such that the conveyor wire belts 64 travel at a faster rate than do the conveyor wire belts 76 that are looped around the rollers 30 of the conveyor 14. Thus, papers leaving the conveyor 14 are traveling at an increased speed as they pass under the pulleys 66.

I have found it advantageous to apply pressure to the papers on the final portion 14 of the conveyor, in order to promote even flow of the papers under the pulleys 66. To this end, papers on the final portion of the conveyor are caused to pass under a downwardly biased wheel 80. In this connection, the wheel 80 is shown as a pulley which is mounted on one end of an arm 82 that is mounted on a shaft 84. In addition, an outwardly extending arm 86 is clamped at its lower end onto the shaft 84, and a compression spring 88 extends between the upper end of the arm 86 and the pin that extends through the center of the wheel 80 and the outer end of the arm 82.

Rotatably mounted rearwardly of the wheel 80 (to the right in the example shown) is a roller 90. As best seen in FIG. 5, conveyor wire 02 is looped around the roller 90 and the wheel 80, whereby the roller and wheel rotate in unison in the same direction, i.e., clockwise. With this arrangement, and regardless of their thicknesses, the forward edges of the papers. are prevented from passing under the wheel until or unless they are a predetermined distance apart. In this latter connection, I have found that in the absence of biasing means ahead of the pulley wheels 66, several newspapers often advance simultaneously, due to friction between the confronting surfaces of overlapping papers, with resulting uneven flow of papers along the infeed section 60 and into the racks 12. Thus, the use of the spring biasing means 80-92 forms an infeed spacing equalizer ahead of the pulleys 66.

By insuring the spacing of the papers passing under the pulleys 66 as above described, accurate counting of the papers is assured. Also, the papers pass into the racks with the same spacing, to assure their proper arc of descent. In this connection, a rotary electromechanical transducer 94 is provided which has spaced fingers disposed in the paths of forward edges of the papers. The forward edge of each paper engages one of the fingers and carries it therewith until the paper passes under the finger. This rotational movement of the finger causes a pulse to be generated, which is fed to a counter. In this connection,

and referring to FIG. 1 along with FIG. 5, a counter mechanism 96 is mounted in the housing 10, and as indicated has an input from the transducer 94. When a predetermined number of papers entering a particular rack 12 have been counted, the counter 96 effects movement of another rack 12 into the path of the flow of papers.

For this latter purpose, there is shown in FIG. 5 a solenoid 100 having a spring biased plunger 102 adapted to be engaged by one of the L-shaped bars of a rack 12 just before the horizontal legs of the rack bars reach the flow of papers. When a rack thus engages the plunger 102, movement of the chain and spracket mechanisms 16-20 is halted. In such case, the motor 22 continues to operate, but the slip clutch 24 functions to prevent overload of the motor.

When the counter has counted a predetermined number, it causes the solenoid 100 to be energized, thereby to retract the plunger 102. Retracting the plunger 102 suddenly causes the rack 12 engaged thereby to drop quickly into the path of the papers. Preferably, the plunger 102 is adapted to undergo limited movement upon being engaged by a rack, thereby to prevent too sudden stopping of the rack. Accordingly, the chain and sprocket mechanism decelerates to a stop, rather than coming to an abrupt halt.

In accordance with my invention, papers passing the transducer 94 are subjected to a controlled arc of descent into the racks 12. Further, the papers are shaped so that they structurally assist in their entry onto the stacker so that by the time a rack approaches the transport rollers 48, i.e., when a rack is in the position shown above the rollers 48 in FIG. 1, the stack of papers thereon is one in which the papers are trued up.

To this end, and referring to FIGS. 4 and 5, I provide a pair of thin arcuate elements that extend on top of the roller 62 that follows the transducer 94. Referring to FIG. 8 along with FIGS. 4 and 5, the lower end of each element 110 is bent horizontally and rests on the upper surface of a shelf-like element 112 having an elongated slot 114 therein. The lower end of the element 110 is adapted to be clamped at 116 to the shelf 112. However, by loosening the clamp, the element 110 can be longitudinally adjusted as desired, and then the clamp is tightened in the desired position of the element 110.

Since the elements 110 extend past the roller 62 as above mentioned, papers passing the transducer 94 are forced to travel over the ends of elements 110 before they descend. As the papers pass over the forward ends of the elements 110, they of course curve downwardly toward the lowering rack 12 in their path. As will be observed, the degree to which the papers curve downwardly in moving out into the space against the back of the rack into which they are to fall is controllable in accordance with the positions of the elements 110. Thus, elements 110 constitute arc modulator elements for the papers.

When papers pass onto a rack 12, the above described means of my invention shape them to keep their various edges aligned. As in prior art practices, the ends of papers carried on the conveyor are already aligned. However, when the papers pass into space toward a rack, my system includes means to keep their ends aligned, and also to insure that the forward and rear edges will be aligned when the stack is completed.

As previously mentioned, tripping the solenoid 100 causes the rack 12 held thereby (shown in phantom in FIG. 5 to drop suddenly into the path of the papers passing over the arc control element 110. The papers entering onto the rack during the first few inches of downward travel thereof are automatically bowed in their centers. In this connection, and referring to FIGS. 3 and 6 along with FIG. 5, the bottom of each rack is shaped to provide a center bow for each of these first few papers. In the illustrations shown, the bottom leg of the center bar 40 of each rack is higher than the corresponding legs of the other bars. In one example, the bars are shaped the same, i.e., the bottom legs of the bars have the same cross section, but the bottom leg of the center bar has an elongated, substantially semicircular rod 120 secured thereto, as indicated at 122 in FIG. 6.

When the first paper enters onto such a rack, it will be seen (FIG. 3) that the center portion of the paper is bowed. Similarly, the next paper conforms to the surface configuration thus imparted to the paper on which it comes to rest. Thus, the center portions of the first few papers are in registry, which automatically insures that their ends are aligned. And since the upright legs of the rack constitute a surface of registry for the edges of the papers striking the back of the rack, both the front and rear edges of the papers entering a rack are trued up.

The bow initiating means on the racks created enough of a bow in the first few papers entering thereon as to permit such papers to be lifted at their outer edges without collapsing. Before the papers in the stack have increased so that such a bow would weaken under their weight, the bow is enlarged and retained while remaining papers to make up the stack are moved onto the rack. Referring to FIGS. 1, 2, 4 and 5, a channel element 126 supported on the housing extends below the infeed section 60. In the example shown, the channel element 126 is hooked at its upper end over the top of a sheet 128 that extends between the sides of the infeed section 60, and is clamped at its lower end to the screen 128, as indicated at 130. With the channel element 126 positioned as shown in FIG. 4, the bottom legs of the middle bars of the racks pass through the channel.

When the bottom leg of the rack reaches the upper end of the channel 126, the outer edges of the few papers on the rack engage the upper end of the channel 126 as the rack continues its downward movement. This results in the center bow of the papers being enlarged as such outer edges glide along the channel. The bow enlargement takes place at the upper end of the channel (FIG. 5) and is retained as the outer edges of the papers glide along the channel as shown in FIG. 1. As the outer edges of the papers clear the lower end of the channel 126, they flatten out. When the last of the papers counted for a stack has cleared the lower end of the channel 126, the rear legs of the rack move to a vertical position, and the rack continues=its downward movement-until the stack thereon has been lowered onto the rollers 48.

Again referring to FIG. 5, another feature of my invention includes means to prevent jamming caused by papers striking the rack that is being held in position by the solenoid 100 preparatory to its dropping into the path of the papers leaving the infeed section 60. In this connection, the papers are conveyed through the infeed section 60 at a suflicient speed to insure that their forward edges will strike the rear of the rack when they pass into space beyond the arc control elements 110. In order to facilitate rapid movement of a rack into the path of the papers, the lower legs of such a rack are held by the solenoid 100 in a position very close to the path of the papers. I have found that papers occasionally tend to are toward the front edges of the lower legs of the rack, and to strike such rack and cause a jam up. To avoid this possibility, I provide spaced guide elements 134 (see FIGS. 4, 5 and 7) which are secured at one end on a rod 136 extending between the sides of the housing in the infeed section 60. The free ends of the elements 134 extend in the path of a rack, immediately below the position in which a rack is held in readiness by the solenoid 100. FIG. 4 shows four such finger elements 134, and they are positioned so that they will not be engaged by any portion of a rack. As best seen in FIG. 5, the elements 134 are adapted to guide papers leaving the arc control elements 110 so that such papers cannot possibly strike the rack that is being held in readiness by the solenoid 100.

Referring again to FIG. 5, the channel 126 is positioned to enlarge the bowed portions of and lift the papers passing along it. A wide variety of papers of various thicknesses are stacked in the desired manner in this position of the channel. This is particularly true of papers of various thicknesses which have only one fold, i.e., at the edges which strike the backs of the racks. As is well known, conventional daily and Sunday editions of newspapers are folded twice. As is apparent, such papers entering a rack 12 have folds at one end, as well as along the edge which strikes the back of the rack. For relatively thick daily and Sunday editions, such folded ends cause the stack to build up higher at that end than at the 0pposite end. I

To compensate for the effects of the folded ends, I prefer to mount the channel 126 to one side of the center of the racks 12- away from the folded ends of the papers entering the racks. Referring to FIGS. 9-11, the channel 126 is shown positioned between the center leg of the rack 12 and the leg next to such center leg. Accordingly, the center bow formed in the papers entering the rack is effectively converted by the channel 126 into a larger how that is disposed to one side of the center of the papers passing along the channel. By thus bowing the papers off center, the portions on either side of the channel 126 are maintained substantially straight as they pass along the channel (see FIG. 11), thereby facilitating their stacking in the desired manner as they leave the lower end of the channel 126. If desired, the channel 126 can be replaced with a single plate.

From the foregoing, it will be apparent that various modifications can be made in the particular structures illustrated and described herein without departing from the spirit and scope of my invention. Accordingly, I do not intend that my invention be limited, but that its scope accord with a reasonable interpretation of the appended claims.

I claim:

1. In combination:

a plurality of racks adapted to be moved vertically downward; means to convey overlapping sheets with aligned ends horizontally into space toward each rack as it enters the path of the sheets and moves downwardly;

means for bowing the sheets intermediate their ends as they enter each rack in its downward movement to permit the sheets to stack up in the rack while maintaining their ends aligned;

arc imparting means over which the sheets move before passing into space for effecting descent of the sheets onto the racks in a controlled arc. I

2. The combination of claim 1, wherein said conveyor means receives the sheets from a feed conveyor, said conveyor means causing the sheets thereon to move at a constant speed that is higher than their speed on said feed conveyor; and means for bearing against the sheets passing onto said conveyor means to overcome surface friction between sheets and cause the sheets advancing along said conveyor means to be evenly spaced.

3. The combination of claim 2, including:

means to stop each rack momentarily before it enters the path of sheets from said conveyor means;

and guide means above said conveyor means extending below the stop position of the racks to prevent sheets from entering a stopped rack.

4. The combination of claim 3, wherein said bowing means further includes said racks, each rack having a platform onto which the sheets stack, said platform being shaped so that a portion intermediate its ends is higher than its ends.

5. The combination of claim 4, wherein:

the platform of each rack is formed of a plurality of spaced fingers, and wherein said bowing means includes a stationary plate element which extends between the ends of adjacent fingers as the rack moves downwardly, said racks and said plate element being so dimensioned that the edges of sheets adjacent the outer ends of said adjacent fingers engage said plate element and are thereby lifted as the rack moves down.

6. The combination of claim 3, including:

means for releasably holding said plate element in place, and permitting said plate element to be releasably held in any of several positions;

and means releasably holding said are imparting means in place, and permitting said are imparting means tobe releasably held in any of several positions.

7. The combination of claim 6, wherein said plate element is formed of a channel.

8. Newspaper stacking apparatus comprising:

substantially vertically oriented rack conveyor means;

spaced racks carried by said conveyor means, each rack having a back and a seat substantially at right angles, said back being attached to said conveyor means, the upper portion of said seat having an intermediate portion that is higher than its ends, whereby a newspaper placed on said seat conforms thereto and is thus bowed intermediate its ends;

the seat of each rack being formed of spaced fingers extending from the lower end of said back, said intermediate portion of the seat being a finger that is higher than the other finger;

and a plate to be releasably held in a stationary position in which adjacent fingers of each seat pass along either side of said plate, said plate being releasably positionable in different positions intermediate the ends of said seats.

9. The combination of claim 8, including:

a conveyor positioned above said plate for conveying overlapping papers therealong and into space toward the back of a rack passing below one end thereof,

said conveyor having spaced rollers and interconnecting spaced belts;

means for operating said conveyor at a constant speed;

and arcuate members spaced between said belts and extending over said roller at said one end of said conveyor, said members being positioned so that papers carried along said conveyor pass onto and over said arcuate members, said arcuate members being adjustable for controlling the arc of descent of papers passing from said one end of said conveyor toward a rack passing below it.

10. The combination of claim 9 including:

means adjacent the other end of said conveyor for separating papers passing thereon so that the forward edges of the papers are evenly spaced;

and spaced guide elements extending above and past said one end of said conveyor toward said racks, said guide elements being positioned so that fingers of said seats pass between them.

References Cited UNITED STATES PATENTS 175,638 4/1876 Ashley 27l86 3,160,413 12/1964 Faeber 271-86 3,292,505 12/1966 Wiseman. 2,677,317 5/1954 Vogt.

EDWARD A. SROKA, Primary Examiner US. Cl. X.R. 

